Iron is one of the micronutrients required by growing plants. Iron is necessary for the production and synthesis of chlorophyll, and for the activation of various enzyme systems. Iron deficiency or what is frequently termed iron chlorosis is most common on alkaline soils in the Western United States. Such a condition results in decreased crop yields, and even results in the death of plants. According to one estimate, at least about 5 percent of the cultivated land west of the Mississippi River is considered iron deficient. Actually, this iron deficiency may not really be caused by a lack of iron in the soil, but rather more precisely from the relatively low solubility of the iron compounds that are present.
Correction of soil iron deficiency with inorganic iron compounds is very difficult, since such are generally quickly converted to insoluble compounds wherein the iron is substantially unavailable to the plant itself. Chelated iron compounds can correct a soil iron deficiency, but the cost of application is prohibitive for most crops, so that such generally are suitable only for specialized small area purposes such as house plants and the like.
Efforts have been made in the past to provide a stabilized-iron high nitrogen high phosphorus fertilizer solution. Relatively small amounts of iron are needed, and it would be convenient to be able to apply it along with the major fertilizer components. Unfortunately, efforts heretofore have simply resulted in materials that have either had large quantities of iron sludge and thus have been difficult to apply, the sludge clogging the feeding equipment, and not providing a source of usable soluble iron for the plants, or the admixtures heretofore prepared have turned into solid gels shortly after preparation, substantially precluding suitable application to the plants.
So far as I am aware, there simply is no commercially available source of stabilized solubilized iron which is effective and yet economical for use on crops.
Thus, it is an objective of my work to develop stable iron-containing solutions suitable for use in correcting soil iron deficiencies. Higher concentrations of iron, usable in the context of a fertilizer formulation, require less liquid per acre to achieve the desired results. Thus, a further objective is to develop a system containing as high a concentration of iron as possible, preferably in conjunction with a high nitrogen high phosphorus containing material.